Form block for box covering machines



Dec. 17, 1957 a. BAIERLEIN 2,

FORM BLOCK FOR BOX COVERING MACHINES Filed NOV. 7, 1955 n F I G. l

I INVENTOR.

BY 014 K yd v M ATTORNEY United 2,816,492 FORM BLOCK FOR BOX COVERING MACHINES George Baierlein, Brooklyn, N. Y., assignor to Imperial Paper Box Corp., Brooklyn, N. Y., a corporation of New York Application November 7, 1955, Serial No. 545,180 3 Claims. (Cl. 93-59) This invention relates to expanding mandrels and relates more particularly to a novel form block for box wrapping machines wherein the vertical side walls are movable outwardly relative'of their supporting base in order to press the side walls of the box shell which has just been covered with a decorative or other wrapper, into firm engagement with presser plates engaging the outer faces of the side walls of the box.

The form block of the present invention is essentially an expanding mandrel but it has particular usefulness in box wrapping machines wherein the box shell is formed of wood or other relatively non-yielding material as contrasted with a paper box shell.

For blocks for use with box wrapping machines are generally made of wood and are of fixed dimensions. It the paper box shells vary in dimensions the form block nevertheless can enter the shell, for the purpose of pressing the marginal edges of the wrapper against the inner faces of the side walls, due primarily to the inherent resiliency of the paper board forming the shell.

When the shell is formed of wood, however, difiiculty is frequently experienced and if the shell is oversize the marginal edges of the wrapper are not pressed into firm adhesive engagement with the inner faces of the side walls of the box.

An important object of the present invention is to provide a novel mandrel or form block with outwardly movable side walls and fluid means including cylinders and pistons for controlling outward movement of the same. By this arrangement the form block in its contracted state can be made somewhat smaller than the inner dimensions of the shell. After the wing sections covering the outer and inner side walls of the box are in place the form block re-enters the box and as the external presser bars move into engagement with the outer faces of the side walls of the box the side walls of the form block simultaneously move outwardly.

Another object of the present invention is to provide a novel expanding mandrel or form block of this character wherein the extent of outward movement is determined by the permissive distance of travel, fluid pressure means being provided which causes each of the side walls of the iorm block to exert an equal pressure on the walls of the In the drawing:

Fig. 1 is a plan view of a form block or mandrel embodying the present invention.

Fig. 2 is a side elevation thereof, partially in section.

The form block of the present invention includes base wall secured at the lower end of a vertically reciprocating plunger 11 forming part of a conventional box wrapping or other type of machine. In the embodiment shown the base wall is rectangular in shape and has movable vertical side walls 12 and end walls 13 of shorter length. Because of this shorter length of the end wall each one is movable outwardly by a single fluid actuated piston whereas the side walls are moved by a plurality of such pistons.

A cylinder 14 is mounted by means of a bracket 15 at each end of the base wall, each cylinder having a piston 16 supporting a piston rod 17 which is suitably connected with the end wall 13. This connection is preferably not completely rigid but is also not so loose as to permit free swinging movement, so that if the adjoining walls do not s atent "ice bear a true right angular relationship to each other or if the opposed external presser elements are not exactly parallel to each other the side and end walls 12-13 nevertheless firmly press the inner flaps in place against the inner faces of the side and end walls of the box.

A fluid conduit 20 is connected with the piston chamber.

Movement of side walls 12 is controlled by pistons 21 and 22 secured to piston rods 23 and 24 in cylinders 25 mounted on brackets 26. Fluid enters midway between the ends of the cylinder through conduit 30. These piston rods are connected at 31 to the movable side walls and here again the connection is preferably not rigid. The movable walls are urged inwardly by means of tension springs 32 connecting the end walls and 33 connecting the side walls.

Conduits 20 and 30 are connected with a common source of fluid under pressure and accordingly outward pressure at all points along the movable side walls of the form block is equalized.

While there have been described herein what are at present considered preferred embodiments of the invention, it will be obvious to those skilled in the art that many modifications and changes may be made therein without departing from the essence of the invention. It is therefore to be understood that the exemplary embodiments are illustrative and not restrictive of the invention, the scope of which is defined in the appended claims, and that all modifications that come within the meaning and range of equivalency of the claims are intended to be included therein.

What I claim is:

1. An expanding form block for box wrapping machines and comprising a rectangular base and means on the machine for supporting the base, end walls and side walls which are carried by the base and which are outwardly movable relative thereto under equalized pressure to press the wrapper against the inner faces of the box, a cylinder provided with a piston and a piston rod mounted at each end of the base longitudinally thereof, the end walls being connected to the outer ends of said piston rods, and spaced cylinders mounted transversely of the base, each being provided with oppositely movable pistons and piston rods whose outer ends are connected with said side walls, and a means for connecting a common source of fluid under pressure with each cylinder.

2. An expanding form block comprising a rectangular base and means for supporting the base, side and end walls which are carried by the base and which are outwardly movable relative thereto under equalized pressure, a cylinder provided with a piston and a piston rod mounted at each end of the base longitudinally thereof, the end walls being loosely carried at the outer ends of said piston rods, and spaced cylinders mounted transversely of the base, each being provided with oppositely movable pistons and piston rods whose outer ends are loosely connected with the side walls of the form block.

3. An expanding mandrel comprising a rectangular base and means for supporting the base, side walls which are carried by the base and which are outwardly movable relative thereto under equalized pressure, a cylinder provided with a piston and piston rod mounted perpendicular to each edge of the base, said side walls being connected with the outer ends of said piston rods, said connection being non-rigid to permit a slight measure of sidewise movement of each side Wall relative to the adjoining edge of the base, and means for connecting a common source of fluid under pressure with each cylinder.

Young Mar. 29, 1892 Kleinsmith May 23, 1933 

